Cold injectors leaking fuel

mje4him · Post by **mje4him** » 05 Jan 2018, 11:28

I think Ive lost my mind working on this, and need some help. I have a 00 V40, 127k miles. Generally good condition. Problem is when temps are below 0F the fuel injectors leak. I just replaced them all. I thought perhaps a faulty regulator might be over pressuring them, so I replaced it as well.
Just went out to start it at -9 and there was fuel everwhere.

Has anyone else seen this?
Possible solutions?

(and yes I replaced the Orings and properly lubed them when replacing the injectors. Its the injectors themselves that are leaking)

Post by **alschnertz** » 06 Jan 2018, 05:13

Could the fuel rail be cracked?
Or maybe the fuel line connection is not sealing?
Can you look as someone else starts it to try and pinpoint the area where it's leaking?

Post by **jimmy57** » 06 Jan 2018, 10:03

I'm discounting that this Volvo could be the roadgoing equivalent of an SR-71 Blackbird (the recon plane that leaks fuel until it gets supersonic and heats and wing tanks seal) .
It leaks at every injector or can you tell? IF you run it does it stop leaking? The fuel pump has a relief valve that opens at 84 psi so the fuel pressure shouldn't go high enough to leak past those top injector fuel o rings. Gasoline is so thin and capillary action will take it away from the actual exit point readily. The plastic housing fuel pressure goes into nd the o ring where is fits into end of fuel rail deserve close checks. You can take fuel line loose and use a rubber tipped blower and pressurize while spraying soapy water to see where bubbles form.

QUARKS40 · Post by **QUARKS40** » 06 Jan 2018, 19:10

You say you just replaced the injectors. Did you use stock 2000 injectors or the 440CC units from the 2001+? The reason I ask is that the O-rings for the '01+ are different from the 2000 model (And yes, using the red 440CC units from an '01 is quite acceptable, even desirable). It goes without saying that you used new O-rings when you changed the injectors.

mje4him · Post by **mje4him** » 16 Jan 2018, 20:22

Replaced with some GB remanufactured injectors (might be the problem)... but the same things happens as the stock.
The vent port on the right hand side is actually squirting/bubbling fuel out.
Does not do this when the fuel pump primes (not running), only when the engine is running.
Not leaking from the fuel rail.

Watched similar injector type on a BMW (same year) do the exact same thing. Only seems to happen at -5F or colder. If I bring them in, warm them up and take them out. They don't leak until a few seconds after the super cold fuel hits them.

I'm thinking a different injector might be in order. I'm gonna take a look at the 440CC injectors and see what they look like.

QUARKS40 · Post by **QUARKS40** » 19 Jan 2018, 22:42

mje4him wrote: ↑16 Jan 2018, 20:22 Replaced with some GB remanufactured injectors (might be the problem)... but the same things happens as the stock.
The vent port on the right hand side is actually squirting/bubbling fuel out.
Does not do this when the fuel pump primes (not running), only when the engine is running.
Not leaking from the fuel rail.

Watched similar injector type on a BMW (same year) do the exact same thing. Only seems to happen at -5F or colder. If I bring them in, warm them up and take them out. They don't leak until a few seconds after the super cold fuel hits them.

I'm thinking a different injector might be in order. I'm gonna take a look at the 440CC injectors and see what they look like.

The red injectors used on the '01+ S40 are the ones you want, hands down. I forget if they're 420CC or 440CC. They do however, use a different o-ring set.
If you have VIDA, look up the o-ring p/n and also, if you have dice, reset the engine adaptation. You'll enjoy these new injectors.
EDIT: any thoughts about the cold weather causing a problem with the intank fuel pressure regulator and/or the FPR located on the fuel rail? Anyone?